London is widely known for being a city of immigrants – famously, a third of its residents were born abroad. It’s not quite so well-known as a city of emigrants. But, at least within the UK, that is its role.

According to internal migration data recently released by the Office for National Statistics, London sees by far the greatest population loss of all the English regions. 242,000 people moved out of London in 2011. When offset against those moving to the capital, this resulted in a net loss of 40,000 people.

In this interactive map, parliamentary constituencies are grouped according to the taxpayers’ mean income from pensions. The constituencies are pooled into five equally-sized groups with those with the richest pensioners shaded darkest, and the poorest pensioners lightest. These can be compared with the party of the current MP for each area.

Scrapping the UK census could seriously undermine politicians’ ability to formulate evidence-based social policy, a committee of MPs has warned.

The Office for National Statistics is currently considering whether to abolish the national census, which has taken place every 10 years since 1801 (except for 1941, when it was cancelled as a result of the Second World War). The government has suggested that the census is too expensive – the 2011 census cost £480m.

Alternative data collection methods under consideration include making greater use of local administrative data sets and internet research methods. The ONS will reach a conclusion in 2014 about whether to carry out the 2021 census.

The Commons Science & Technology Committee has looked into the possible alternatives to the census. In a new report, it said that the social science benefits of the census “outweigh the financial costs”. It was “not convinced that the use of administrative data would be a cheaper option over a 10-year census cycle”, it said. Read more

The argument about GCSE English grades continues to boil away. Legal actions are commencing. The attention has uncovered clues that exam reforms over the past few years have, by accident, been more substantial than ministers or officials had intended. The marking system used for the old O-level might have been reintroduced by stealth – and accident.

Here’s why: English exams used to deploy a process called “norm referencing” (or “marking on a curve”). That means that, in effect, you hand out grades depending on their position. In 1963, it was decided that roughly the top 10 per cent of A-level entrants would get an A, the next 15 per cent a B and so on.

Since the 1980s, exams have used “criterion referencing”. That is to say, they say “if you know the date of the Battle of Hastings, that is worth an C. If you know about William the Conqueror’s claim on the throne, you get a B. If you know about Hardrada, get an A…” Under this model, you can have changing numbers of pupils getting each grade.

This graph, from Alan Smithers at Buckingham, shows what happened when England switched from one to the other in the late 1980s.

The Office for National Statistics has expressed concern over the quality and timeliness of some official housing market data.

In the second stage of the ONS’s review of housing market statistics, which has just been published, it calls for greater accessibility of housing-related stats, more availability and greater punctuality of local-level figures, and the introduction of a private rental price index. Read more

In July Japan exported a higher value of goods to China than to Europe or to north America. It also imported a higher value of goods from China than from north America and Europe combined, and about the same amount as from the rest of Asia combined. Read more

At the heart of the issue is the realisation that the RPI formula is deficient and out-of-date. Continuing with the current method is the equivalent of Britain still thinking a 1970s Austin Allegro is cool, while the rest of the world is driving the latest Mini.

After rooting around in a Leicester car park, a group of academics have found a scoliosis-racked body with battle wounds. They think it might be Richard III: DNA tests await. If it is him, what do you do with him? On the one hand, he was a king. A long time ago, yes. But a king’s a king, right? And he has something of a following.

On the other hand, he is rather implicated in child-murder – and he was killed by his successor. If we think the suspected murder victims were legitimate kings and his successor, Henry VII, was as well, how do we treat Richard III? These are not straightforward problems. Perhaps we should ask the family. Read more

The difference between the promising employment data and the bearish economic figures could be partially explained by the fact that the headline employment data do not capture elements of the labour market such as inactivity rates and forms of non-full labour utilisation, including part-time workers that were not able to find a full-time job (‘involuntary part-time workers’).

According to OECD data, the UK has had a particularly fast upsurge of involuntary part-time workers, rising from 1.5 per cent of all employed people in 2004 – well below the average share for Europe or the OECD – to nearly 4 per cent last year, above both regions. The UK still has a lower proportion of involuntary part-time workers than peripheral European countries including Italy, and lower than Japan, but it is above most continental European countries including France and Germany and it is higher than that of the US.

The rate at which Britons are living into very old age is rising much more slowly than had been forecast only two years ago, a blow for those hoping for a very long life but good news for pension providers and the Treasury which spend hefty sums on the oldest old.

The numbers of those aged 85 to 89 are about 2 per cent lower than had been forecast in 2010 while the number of those over the age of 90 is some 15 per cent lower than expected, according to analysis of 2011 census data published in July.

The findings suggest that projections in recent years for increased life-expectancy among Britons may have been overdone – with potentially big implications for public policy and the long-term fiscal outlook.

“This means that life expectancy at age 65 should be slightly lower,” said Richard Willets, head of longevity at Friends Life, the life assurance provider, who spotted the discrepancy between 2011 census data and previous demographic projections.

Savills’ latest World Cities Review is out, offering some interesting comparisons between the world’s top urban areas.

Savills looked at the overall cost of running a business in each of the cities, with two different types of firm examined: finance and business services, and creative. For the first time this includes the cost of both office space and residential accommodation for staff. The intention is to offer a useful benchmark for globally-mobile companies.

Unsurprisingly, Hong Kong, New York, Paris and London are the priciest cities by Savills’ measure. Although there is an obvious overall correlation between costs for the two types of firms, a couple of variations stand out: Hong Kong looks relatively cheap for creatives, compared to what finance firms pay; and Paris is either over-priced for creatives or underpriced for financial firms.

Another month of disappointing China trade data: on Monday, overall Chinese exports increased just 2.7 per cent in August from a year earlier, and imports dropped 2.6 per cent. Export growth was higher than July’s worrying 1 per cent, but it’s still far from the double-digit growth that was once the norm. Read more

There is a chart regarding the UK economy which has become so ubiquitous it is known in our office simply as “the Niesr chart”, because it is often republished by the National Institute of Economic and Social Research. It is supposed to be a clear and concise account of Britain’s recent economic woes, putting the recession into accurate context of past recessions. It shows the current recession as the longest and nearly the deepest since the start of the 1930s. People don’t generally know that in the UK the 1920s recession was much worse, but I’ll leave that for now.

Here is the latest version of “the Niesr chart”, published today. Take a good look at it before I tell you why I have begun to become irritated by it.

It is arresting because it does most things right. It is simple to understand. It is clearly drawn and obviously in context. The problem is that that the Niesr chart might be showing us irrelevant nonsense. It is also not a sufficient description of the UK’s recession.

For market traders, economists, and data geeks alike, Friday is one of the highlights of the month – non-farm payrolls day.

For the uninitiated this is the release of data on US jobs growth over the previous month – more properly called the Employment Situation report - published by the Bureau of Labor Statistics, usually on the first Friday of the month following the data (i.e Friday’s new data will be for August).

It is undoubtedly the most eagerly awaited monthly data by world markets and has attained a totemic status, perhaps beyond its real importance. Morning trading volumes are slim in European markets on the day of release as they await the afternoon release time (8.30am Eastern Time in the US).

Why do non-US markets care so much? Well if China continues to grow at current levels then the US will surrender its status as the world’s largest economy in the next decade (and probably in the current decade if measured in purchasing power parity terms). For now though, the US remains the bellwether of the world economy, accounting for a fifth of global output.

Should we care as much as the markets seem to? How important are these numbers? What should we be looking for? Read more

Export growth to non-European markets contrasts with a stagnating or contracting trend of Italian exports to Europe since the start of this year and an underperforming trend over the last decade.

But not all regions contributed in the same way to the export rise. In the first quarter of this year Tuscany, Sicily and Emilia Romagna were among the largest contributors. In Tuscany, the export growth to non-European markets grew at an annual rate of nearly 20 per cent, while the exports of the islands to the same markets were around 50 per cent bigger than the same period the previous year.

Statisticians are accustomed to presenting ministers and senior officials with hard facts, but at the annual gathering of the profession this week in Telford, they were facing tough choices themselves.

Addressing the Royal Statistical Society annual conference, Andrew Dilnot, the chairman of the UK Statistics Authority delighted the audience with a robust defence of the importance of communicating quality official statistics to ministers and the public, but warned that spending cuts would prevent the Office for National Statistics from doing everything it might like.

So, we now know where free schools are going, I thought that I would quickly illustrate a curiosity about them. This map of local authorities is coloured by the performance of FSM-eligible children (a marker of poverty). Red is poor performance and blue good. Free schools are green.

I have chosen this measure because it’s a simple like-for-like metric. Differences are not scores simply accounted for by the fact that some areas have more poor children: I am looking only at deprived pupils’ attainment. This is a quick and dirty way to gauge LAs. Red areas, broadly speaking, are underperforming. Read more

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